The overall objective of this study is to obtain a comprehensive analysis of the protein composition of the plasma membranes of the ocular lens and of related changes that may be associated with development. The specific objectives are to study the plasma membranes of the annular pad and fiber cells of the lens with respect to: a) protein composition, b) rate of membrane protein turnover, and c) related changes in a) and b) associated with lens development, including differentiation and ageing. The methods to be used include: polyacrylamide gel electrophoresis, immuno-electron microscopy, organ culture, radioisotope incorporation with liquid scintillation counting, immunology, and protein fractionation.